CVE-2025-69227 MEDIUM

CVE-2025-69227: AIOHTTP vulnerable to DoS when bypassing asserts

Vendor Aio-Libs
Product aiohttp
Weakness CWE-835
Published January 5, 2026
Last update January 6, 2026

CVSS base score

6.6/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U

What the vulnerability does

01Description

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Versions 3.13.2 and below allow for an infinite loop to occur when assert statements are bypassed, resulting in a DoS attack when processing a POST body. If optimizations are enabled (-O or PYTHONOPTIMIZE=1), and the application includes a handler that uses the Request.post() method, then an attacker may be able to execute a DoS attack with a specially crafted message. This issue is fixed in version 3.13.3.

Key dates

02Disclosure timeline

January 5, 2026 CVE published
January 6, 2026 Record updated